624 



BOTANY 



TART II 



FIG. 623. Euphorbia Lathyris. A, Cyathium (x 5). B, Cyathium cut through longitudinally 

 '( x 7). C, Fruit after dehiscence showing the central column (c). D, Seed in longitudinal 

 section showing the embryo embedded in the endosperm ; ca, caruncula ( x 4). (A-D after 

 BAILLON.) 



ovary formed of three carpels; in each loculus are one or two 

 pendulous ovules with a ventral raphe, 

 and the micropyle directed upwards 

 and outwards. 



The micropyle is covered by a placental 

 outgrowth called the obturator (Fig. 621) ; 

 this assists in conducting and nourishing the 

 pollen-tube, and disappears after fertilisation 

 (of. p. 573). The CARUNCULA, which is formed 

 from the outer integument (Fig. 567 ), 



FIG. 624. Diagram of a dichasial branch of Euphor- 

 bia, with three cyathia, only the middle one of 

 which has a fertile female flower. (After EICHLER.) 



FIG. 625. Euphorbia resinifera. (Nat. size. 

 After BKBG and SCHMIDT.) 



